Chemical Mechanical Polishing (CMP) processes are widely used in the fabrication of integrated circuits. When an integrated circuit is built up layer by layer on the surface of a semiconductor wafer, CMP processes are used to planarize the topmost layer to provide a planar surface for subsequent steps in the fabrication process. CMP processes are carried out by polishing the wafer surface against a polishing pad. A slurry containing both abrasive particles and reactive chemicals is applied to the polishing pad. The relative movement of the polishing pad and the wafer surface coupled with the reactive chemicals in the slurry allows the CMP process to planarize or polish the wafer surface by means of both physical and chemical forces.
After a CMP process, the polished wafer surface is cleaned to remove CMP residue, such as organic matter and abrasive slurry particles, in order that the surface be made ready for subsequent photolithography processes and other steps in the fabrication process. In conventional post-CMP cleaning processes, brushes are used to remove the residue on the polished wafers. The brushes are typically formed of sponges.
Although existing apparatuses and methods for a post-CMP cleaning process have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects. Consequently, it is desirable that a solution for performing a post-CMP cleaning process be provided.